Transmission



June 13, 1944. A. J. MEYER ETAL TRANSMISSION Filed Jan. 25, 1940 4Sheets-Sheet 1 zkiA'lTRNEY.

June 13, 1944. A. J. MEYER ETAL. I

TRANSMISSION Filed Jan. 23, 1940 4 Sheets-Sheet 2 A. J. MEYER ET'AL2,351,061

TRANSMISSION Filed Jan. 23. 1940 4 Sheets-Sheet 5 June 13, 1944.

. IT. R 5w m IX IIV June 13, 1944. A. J. MEYER ETAL 2,351,061

' TRANSMISSION Filed Jan. 23, 1940 4 Sheets-Sheet 4 Patented June 13,1944 TRANSMISSION Andr J. Meyer and Ross E. Taylor, Lexington, Ky.,assignors to Mawen Motor Corporation, New York, N. Y., a corporation ofDelaware Application January 23, 1940, Serial No. 315,148

Claims. (01. 74-268) -to a driving axle, particularly a vehicle axle,

with the engine located Very close to the axle, this latter beingparticularly important for vehicles for'which front wheel drive isdesired and also for vehicles where with rear wheel drive the engine isplaced at the rear of the vehicle.

A further object is to provide a transmission of the character underconsideration in which the drive in each of the several speed ratiosprovided is positive in its nature, and a still further object is toprovide a complete powertransmitting unit in which the transmission iscombined in 7 novel manner with a clutch in such a way that the entireunit may advantageously and compactly be mounted together with an engineto secure a complete power plant taking up the minimum amount of space.

In order to attain the above general objects and other and more detailedobjects which will hereinafter appear, the invention contemplates 'theprovision of planetary gear mechanism with which there is operativelyassociated a plurality of positively engaging clutch and brakemechanisms selectively shiftable into and out of engagement to providedifl'erent drives through the planetary mechanism to obtain the desireddifferent speed ratios between the driving and the driven elements ofthe transmission.

For a better understanding of the detailed nature of the invention andthe manner in which, it may be carried into effect, reference may bestbe had to the ensuing description of suitable forms of apparatusembodying the principles of the invention, illustrated in theaccompanying drawings forming a part hereof.

In the drawings:

Fig. 1 is a central longitudinal section of one example of transmissionand clutch assembly embodying the invention;

Fig. 2 is a similar section on larger scale showing a part of themechanism illustrated in Fig. 1;

Fig. 3 is a section taken on the lines 3-3 of Figs. 1 and 2;

Fig. 4 is a section taken on the line 4-4 of Fig. 1;

Fig. 5 is a section taken on the line 5-5 of Fig. 1;

Fig. 6 is a view similar to Fig. 1, showing another iorm of transmissionembodying the invention;

Fig. '1 is a view on a larger scale of a part of the mechanism shown inFig. 6;

Fig. 8 is a fragmentary cross section taken on line 8-8 of Figs. 6 and7; and

Fig. 9 is a view taken on the line 99 of Fig. 6.

Referring now to the drawings, the transmission illustrated comprises agear case In which in the form illustrated is of the usual automotivetype, being belied at one end for attachment to thecrankcase structureof an engine, the crankshaft of the engine to which the deviceisattached being indicated at l2.

Before proceeding with the description of the change speed gear, a briefdescription will first be given of the clutch with which the gearing isassociated, the details of which clutch form, per se, no part of thepresent invention, but which constitute the claimed subject matter ofapplication Serial No. 315,138, filed January 23, 1940, in the name ofWillis Merle Carter. The particular clutch structure illustrated hereinis, however, particularly advantageously combined with the gearingillustrated to provide a complete power unit which is axially extremelycOmpact in overall dimensions and in which such compactness is obtainedby novel cooperative relationship between certain of the elements of theclutch structure and major elements of the gear structure.

In the arrangement shown, the driving member ll of the clutch is offlywheel like form, having a hub portion l6, keyed as at Hi to thecrankshaft l2, and retained thereon by the retainin nut 20.

Member I4 is provided with a plurality of circular recesses 22peripherally spaced and equidistantly spaced from the axis of theclutch. In each of these recesses there is located a freely rotatablepinion 24 which fits snugly in the recess and is retained axially inplace by means of an annular retaining plate 26 secured to member M bymeans of bolts 28 or other suitable securing means. Member i4 is furtherprovided with a. central recess 38, the perimeter of which recessintersects the recesses in which the pinions. 24 are located. The drivenmember 32 is situated and freely rotatable in recess 30, the outerperimeter of this member being in the form of a gear 34 of the samediameter as that of the recess in which the gear is located. Member 32is axially retained in the recess by the inner part of the retainingplate 26 and the teeth of the gear 34 mesh with the pinions 24.

The hub portion of member $14 is provided with an annular channel 38which is placed, by means of the bore 38 and branch connection 381:. inthe crankshaft, in communication with the lubricating system of theengine. A series of sets oi radial bores extend outwardly from thechannel 38, these bores being arranged in pairs and there being one pairfor each pinion recess 22. One of such pairs of bores is shown in Fig.and comprises what may be termed an inlet passage 42 which is connectedwith the recess 22 at one side thereof by an'inlet chamber 42 hollowedout of member i4. The other bore of the pair provides what may be termedan outlet passage 44 which is placed in communication with the otherside of the recess 22 by means of an ontlet chamber 40. Advantageously,although not necessarily, a balancing chamber 48 is provided at the sideor the recess 22 opposite the outlet chamber ll, this balancing chamberextending along the length or the recess and being placed incommunication with the outlet chamber by means of a passage 54 formed inmember i4 at one end of the recess. The radially outer ends oi. thebores i'orming the passages 44 and 44 are closed by any suitable meanssuch as the threaded plugs 52.

Each of the outlet passages 44 is controlled by means of a plug typevalve 54 mounted to slide axially in the member l4, each of said valvesbeing provided with a balancing head 54a and thelet passages 44 providefor substantially free flow of fluid therethrough when the valves are inthe position shown in the figure. When the valves areshiited from theposition shown to the right as viewed in Fig. 1, flow through thesepassages will progressively be obstructed until such flow is finally cutoil.

The operation of the clutch is as follows, assuming the several passagesand recesses to be illled with operatingliquid which in this instancewould be oil from the lubricating system of the engine.

If the driven member 32 of the clutch is stationary, and the drivingmember is rotated by the engine in clockwise direction as viewed in Fig.5, it will be evident from this figure that the several pinions 24 willlikewise be rotated in clockwise direction about their own axis.Rotating in this manner, these pinions, meshing with the stationary gear24, will operate'as positive displacement gear pumps drawing liquid fromthe inlet passages 42 and carrying this liquid around in the toothspaces of the pinions 24 to be discharged to the outlet passages 44 asthe teethof the pinions come into mesh with the teeth of the gear 34. Ifthe valves 54 are open, the pumping action will result in what may besaid to be closed'circulation of liquid with respect to each of thepumps and inasmuch as the pinions are freely rotatable in theirrecesses, a negligible amount of driving force will be transmitted fromthe driving to the driven member of the clutch.

It now the valves 54 are moved toward closed position, increasedresistance to flow of the liquid discharged from the pumps will beproduced.

This will in turn impose resistance to rotation 01 the pinions 24 abouttheir own axes, and they will thus act to transmit driving force ortorque from the driving to the driven member, the value of this torqueincreasing as the resistance to discharge of liquid from the pumpsincreases.

01' liquid from the pumps is cut of and the pinions prevented fromrotating around their own axes. When they are thus held against rotationthey act as direct force transmitting members for transmitting thedriving force from the driving to the driven member of the clutch, thelatter members under this condition rotati g in unison except for suchnegligible slip as may occur as the result of any turning of the pinionspermitted by slight leakage of liquid past the ends of the pinions andbetween the ends of the gear teeth and the walls of the recesses inwhich the gears are housed. Since the liquid is a inbricant, however,the gear and pinions may be fitted with close tolerances and the amountof leakage held to a negligible value.

While the pinions may, if desired, be mounted to. rotate on spindles,they are preferably permitted to float in their respective recesses inorder to provide the simplest possible construction, and in order toeliminate or reduce to a minimum the side thrust on the pinions due-tothe'delivery pressure when the control valves are closed, the balancingchambers 48 are provided.

As will be observed from Fig. 1, the balanced nature of the controlvalve eliminates axial thrust on the valves due to fluid pressure andconsequently, the force necessary to. .be applied to the shift ring 56to move it or to hold it in any given position of adjustment isrelatively very slight, thus making the clutch extremely easy tocontrol. The number of pinions and associated passages and valves mayobviously be varied depending upon the size of the clutch and the amountof power to be transmittedtherethrough. Ordinarily, a series of three orfour pinions will be employed in a clutch mechanism suitable for usualautomotive use.

Referring now/more particularly to Figs. 2 and 3, the gearing with whichthe above described clutch is associated comprises a single planetarygear set consisting of an outer ring gear member SI having internal gearteeth 62 which mesh with a series of planets 64 having teeth 66. Theplanets are mounted on suitable pins 68 mounted in a planet carrier I0and the planet teeth 68 also mesh with the teeth I2 of a central sungear member I4.

The sun gear member 14 is annular in form and has a radially extendingdisc-like portion 14a. provided at its circumference with a series ofteeth 16 forming one part of a positively engaging dog type clutch to behereinafter more fully described. A portion 14b extends axially from theportion 14a to provide a bearing face 140 adapted to bear against aradial face on the I driving member H of the clutch and as will be theengaging elements of a positively engaging dog type brake which will bedescribed; later.

The planet carrier is provided with awhub portion 10a journaled on acentral rotationally stationary shaft 80. and carries a set of internalteeth 82 which form one element of a positively engaging dog type brake.

The hub portion Illa of the carrier 10 has a set of external splines 84which engage intern'al splines 88 formed on an annular shift member 88,the latter being mounted to be shifted axially of the gearing.

When valves 54 are'fully closed, the circulation The ring gear. member60 is of cup-like form,

having a radially extending portion 60a, between which and the radiallyextending portion 144: of the sun gear member the planet carrier 10 isretained, and a hub portion 60b carrying external splines and a set ofinternal teeth 82, the latter forming one element of still anotherpositively engaging dog clutch. The hub portion 80b carries an axiallymovable shift member 94 having internal splines 86 engaging the splines90 on they At its forward end the sleeve I06 is provided with,

a set of external splines I08 which are engaged by the splines 86 of theshift member 88. Splines 86, which also engage splines 84 on the planetcarrier in some positions of member 88, operate at such times to providea direct coupling between the planet carrier and the driven element.

fort I22 engaging an external groove in member 84.

' The driven sleeve I06 is carried in suitable bearings I24 and I86mounted in the casing I0 and servesto radially support and locate thecentral shaft 80 which extends beyond the end of the sleeve. Theprojecting end of the shaft is 1 splined at I26 to engage internalsplines -I40 on a shift member I42 having external splines I44 slidablyengaging internal splines I46 carried by a mounting member I48 bolted tothe casing I0 by means of the bolts I60. The shift member I40 isprovided with portions I42a overlying the end of the shaft 80 and isrigidly fixed against axial displacement relative to the shaft by meansof a retaining member which may advantageously be in the form of alocking ring I62.

The shift member-88 at its forward end is provvided with a set ofexternal teeth 82a adapted to mesh with the internal teeth 82 on thering gear member to provide a positively engaging clutch, and this shiftmember further is provided with a set of external splines IIO engaging aset of internal splines I I2 on a shiftable clutch member I I4 engagedby a part 94a of the shift member 94 so as to be axially shiftable withthe latter memher. The clutch member H4 is provided with a through alongitudinally extending slot I20 in the driven slee've I06, the outerend of this pin being situated in a suitable bore in the shift member88.

Shaft 00, which is axially shiftable, is provided at its forward endwith a set of external teeth 80a adapted to selectively engage eitherthe teeth 18 on the sun gear member to provide a positively engaging dogtype brake, or teeth 82 on the planet carrier 10 to provide a diflerentpositive! engaging dog type brake.

The driven member 32 of the main clutch, which constitutes the drivingelement of the transmission, is provided with a hub portion 32ahaving aset of internal splines I2I formed thereon which engage externalsplines. I22 formed on a shift member I28 encircling the planetary gearset. The shift member I24 is provided with a set of internal teeth 16aadapted to engage the teeth 16 on the sun gear member 14 to form apositively engaging 'dog clutch and is further pro vided with a secondset of internal teeth 63a adapted to engage the external teeth 63 on thering gear member to provide still another positively engaging dogclutch.

Referring now more particularly to Fig. 1, it

will be observed that the position of the shift member I24 is controlledby means of a shift rod I26 slidably mounted in the casing I0 and havingfixed thereon a shift fork I28 engaging a suitable external groove inthe shift member.

The shift member 84 is controlled by a second The shift member I42 isengaged by a shift I fork I64 carried by a third shift rod I56 slidablymounted in the casing.

The shift rod I26, I 20,- and I66 are mounted so that their center linesare on the arc of a circle, as illustrated in Fig. 4, and rod I26, whichis located between the other two rods, is provided with a transverselyextending slot I60 while rod I80 is provided with a similar slot I62 androd I86 is provided with slot I64. Slots I60, I62, and I64 are arrangedto be selectively engaged by means of a selector member I66 ofsector-like form, slidably and turnably mounted on shaft I68 which iscarried in the cover plate (not shown) for the casing I0, parts of whichplate are indicated diagrammatically at I10. The selector member I66 isprovided with a suitable knob'portion I12 adapted to be connected to anydesired form 01' control member for actuating the selector.

For effecting final drive in a vehicle, the sleeve I06 is, in theembodiment illustrated, provided with a worm I14 adapted to mesh with anaxle worm gear I16 for transmitting drive to one or more transverselyextending live axles, the center line of which is indicated at I18. Theone compact casing I0 may therefore serve to house the clutch, thetransmission and the main axle I gear.

' From Fig. 4 it will be observed that the arclockwise direction fromthe position shown.

The operation of the apparatus in order to selectively obtain thevarious desired drives through the transmission is as follows:

In the position of the parts shown in Figs. 1 and 2, the parts areall inneutral position and it will be observed that the shift member I24 is inengagement only with the driven member of the clutch to which it issplined so that no power is transmitted beyond this shift member. Theshift member 88 is in a position such that its internal splines connectthe driven sleeve I06 and the planet .carrier 10 so that the latter isrotatable with the sleeve. However, none of the clutch forming teethassociated either with this shift member or with the planet carrier arein engagement so that these parts can rotate freely to permit freedom ofmovement of vehicle wheels or any other driven elements drivslidablymounted shift rod I30 carrying a shift ingly connected to the sleeveI06.

Let it be assumed now that the transmission is incorporated in a vehicledrive and it is desired to set the gear to provide for forward drivewith maxumum ratio of speed reduction between the driving and the drivenshafts. To effect this, the selector is turned colmter-clockwise toengage the shift rods I20 and I and is then moved to the right as viewedin Fig. 1 to simultaneously move these two shift rods and the shiftmembers 94 and I24 to the right. This shift connects the shift memberI24 to the sun gear member of the gear set through the clutch providedby the teeth I and Ila. It also effects engagement of teeth 08 on theshift member 84 with the stationary teeth I00 onthe ring I02. Since theshift member I24 is splined to the driven member of the main clutch,power is transmitted to the sun gear when the main clutch is engaged,and since the shift member 94 is splined to the hub of the ring gear,this latter gear is held stationary. Assuming the main clutch to beengaged so that the sun gear is rotated, the drive will be transmittedthrough this gear to the planet pinions which, rolling on the stationaryringgear, will cause the planet carrier to rotate in the same directionas the sun gear but at greatly reduced speed. Shifting of the member 04to the right does not operate to shift the member 80 axially, since theaxial position of this member is determined by the 3 axial position ofthe central shaft 80, which under the assumed conditions has not beenmoved from its neutral position. Therefore, the hub of the planetcarrier is drivingly connected to the sleeve I06 by member 88, thesplines of which engage both this hub and the sleeve. Forward drive atlow speed, which may for convenience be referred to as first speed, isthus effected to the driven element of the transmission.

In order to effect forward speed with a lower ratio of gear reduction,which may be conveniently referredto' as second speed, the selector isfirst returned to neutral position and thereafter rotated from theneutral position in clockwise direction to engage the shift rods I26 andI56. After these rods are engaged they are shifted to the left by meansof the selector. This action causes the central shaft 80 to be moved tothe left from the neutral position shown, so as to cause engagementbetween the teeth 000 on the shaft and the internal teeth I8 on the sungear member I4. The sun gear is thus held against rotation because ofthe fact that the central shaft is held against rotation through theengagement of the shift member I42 which is splined to the casing.

Shift to the left of the rod I20-causes engagement between the teeth63:: on the shift member I24 and the teeth 63 on the ring gear member60. Drive is thus transmitted through the shift member I24 from thedriven member 32 of the main clutch to the ring gear, and rotation ofthe latter causes the planets to roll ,on the fixed sun gear 14 torotate the planet carrier in the same' direction as the ring gear. withthe sun gear stationary and the ring gear rotating, the diiference'inspeed of rotation between the ring gear and the planet carrier will beless than the difference in speed of rotation between the sun gear andthe planet carrier under the first speed drive conditions, so that underthe presently assumed conditions a second speed having less gearreduction is provided. when shaft 80 is shifted to the left it not onlyengages the sun gear to hold the latter stationary, but through the pinI I8 it also moves the member 00 to the left. This member slides axiallyrelative to the clutch member 4, due 5 to the, splined connection no,II2 between these parts. part I I4 being retained in its neutralposition because of its connection to shift member 94, which is notshifted from neutral position. The only effect of moving the member 00to the left from its neutral pomtion is to increase the axial length ofengagement of its splines with the hub of the planet carrier, this hubremaining splined to the driven sleeve I00 so that the If drivetransmitted to the planet carrier is transmitted through member 00 tothe driven element. In order to effect direct drive through thetransmission at 1:1 speed ratio, the selector, after having beenreturned to neutral position, is turned counter-clockwise to engageshift rods I26 and I30 and is then moved to the left. This movementcauses'teeth "a on the shift member I24 to engage teeth 63 on the ringgear member so as to transmit drive from the main clutch to the latter.Movement of the shift member 94 to the left causes teeth 92b to engagethe teeth 92 on the hub of the ring gear member 00 and a direct drivingconnection between the ring gear member and the sleeve I06 is thuseffected through the member 4, which is splined to member 80. the latterin turn bein splined to the sleeve I00. Since under this condition thesun gear member is not drivingly connected to any other part orrestrained against rotation by engagement with the shaft 80, nointerference with the direct driving connection through the transmissionis brought about by the planetary gearing, the planet carrier of whichrotates in unison with the ring 0 gear because of the connection betweenthe sleeve I08 and the hub of the carrier provided by the splined member00. With the ring gear and planet carrier rotating in unison, the sungear will also rotate in unison with the other parts, which it is freeto do. Thus, in direct drive, there is no relative rotation between anyof the gears of the planetary set, which revolves as a unit.

In order to effect reverse drive, the selector, after being returned toneutral position, is turned in clockwise direction to engage the shiftrods I 26 and IE0 and is thereafter moved to shift these rods to theright. This movement operates to cause the teeth 80a on the rotationallystationary shaft 00 to engage teeth 82 on the planet carrier,

thus locking the latter against rotation. Movement of shaft 80 to theright also shifts the splined member 00 to the right so that this memberis no longer in engagement with the splines 84 on the hub of the planetcarrier, thus permitting the driven sleeve I00 to be rotated while theplanet carrier is held stationary by shaft 80.

Movement to the right of the shift rod I26 and its associated shiftmember I24 effects engagement between the teeth I6 and 16a to transmitdrive from the driven member of the main clutch through this shiftmember to the sun gear member 14. With this gear driven by the source ofpower and with the planet carrier held station- 0 my, it will be evidentthat the ring gear member 60 will be caused to rotate in the oppositedirection and at reduced speed because of the dinerence in diameters ofthe sun and ring gears.

The movement of shaft to the right,'which through the section of pin IIIshifts member 80 drives and including a direct drive forward top speedis provided.

Referring now to the form of transmission show in Figs. 6 to 9,inclusive. the clutch construction is the same as previously describedin connection with Fig. 1, the parts being correspondingly numbered, andtherefore need not again bedescribed in detail.

In the present form, a central shaft 200 is provided, around which isrotatably mounted the driven sleeve 202 carrying the gear 204 adaptedto' mesh with the axle gear indicated at 206 mounted to turn about axis208. As in the embodiment shown in Fig. 1, the transmission and axlegear parts are mounted in a common housing M0.

At its forward end, shaft 200 carries a gear 212 constituting the sungear of a planetarygear train. This sun gear is in constant mesh with aset of planet pinions 2M mounted in a planet carrier 2%. Pinions 211ialso mesh with a ring gear member tit having a radially projectingflange splined to the driven member 320. of the,

main clutch which constitutes the driving eleplanet pinions 222 meshwith a second ring gear member 226. v

The planet carrier 224 has a forwardly projecting cup-like extension2240 which carries a set of external teeth 228 forming part of apositively engaging clutch mechanism, later to be describedmore fully.This planet carrier also is provided at its rearward end with a set ofexternal teeth 230.

As will be seen from Figs. 6 and '1, the planet carrier 224 has aportion which is U-shaped in cross-section, the arms of this portionserving to axially locate the ring gear 226. This gear carries a set ofexternal teeth 232 forming one of the clutching elements of anotherpositively engaging clutch.

A hub 234 is splined on the driven sleeve 202 rearwardly of the carrierhub 216a. Hub 234 is provided with external splines 236 which areslidably engaged by internal splines on a shift member 238. Member 238has an outer clyindrical part 240 provided with internal teeth 242meshing with teeth 230 on planet carrier 224. A second shift member 244of generally cylindrical form has a portion 244a encircling the portion240 of the first shift member, the two shift members being rotatablewith respect to each other and being rigidly fixed against axialdisplacement with respect to each other by a retaining on the member 244the portion 240 of member 2881s held. v

At its forward end the shift member 244 is provided with externalsplines 248 engaging internal splines on the casing 210. It is furtherprovided with a set of internal splines or teeth 2" (see Fig. 8)engaging external splines 252 on a synchronizing ring 255 which isreleasably held against axial displacement with respect to the shiftmember 2 by means of a ball 250 loaded by means of spring 258. Thesplines 252 on the synchronizing ring are notched to receive ball 250.

The ends of ring 360 are beveled. One of the beveled ends is adapted tofrictionally engage a mating friction ring 260 of suitable material suchas bronze or the like secured to the ring gear member 226. The other endof ring 254 is adapted to engage a similar friction ring 202 secured tothe planet carrier 224. When ring 254 is in its axially centralposition, it is out of engagemerit with both of the friction rings 260and 252.

Referring now more particularly to'Fig. 6, the rearward end of thedriven sleeve 202 has splined thereon a clutch member 26d carrying aring of external clutch teeth 2%. The rearward end of the casing hasfixed thereto a brake member 2% carrying a ring of external brake teeth210. Teeth 288 and 210 are on the same diameter and between them thereis mounted the shift member 212. The shift member 212 is carried by a Isynchronizing ring 2141 which is internally splined to a carrier 218which is inturn rigidly fixed to the rearward end of the central shaft200. The synchronizer ring 214 is provided with beveled friction rings21B and 200, respectively adapted to engage suitable beveled facesprovided on the clutch part 266 and brake part 208, depending upon whichdirection the synchronizing ring is shifted from its neutral or midposition, in which 40 position the friction rings are out of contactwith ring 240 between which and a suitable shoulder each other. Theteeth or splines on the shift member 212 which engage the splines on thesynchronizing ring are adapted to mesh alternatively with teeth 206 orteeth 210 depending upon the direction of shift of the shift member fromits mid position.

A ball 282 loaded by spring 284 is adapted to seat in the suitablynotched internal teeth 288 on the shift member 212 'to releasably holdthe synchronizing ring 216 against axial displacement with respect tothe shift member 212.

The shift member 238, at the forward end of the transmission, is shiftedby means of a shift rod 288 slidably mounted for axial movement insuitable bearings in the transmission casing, and the shift member 212at the rear of the transmission is shifted by means of shift rod 290likewise mounted in the casing. The shift rods 288 and 290 arearranged'parallel to each other and are notched respectively at 282 and284 (as seen in Fig. 9), to be selectively engaged and shifted axiallyto the right or left, as viewed in Fig. 6, by means of a shift lever 286of conventional form carried by the casing cover plate 290.

The operation of this form of the transmission, which like thepreviously described form provides three forward speeds including a.direct drive,

and a reverse speed, is as follows:

To obtain forward drive with maximum speed reduction through thetransmission; ordinarily referred to as first speed, the shift rod 288is engaged and shifted to the right from the position shown in Figs. 6and 7. 'This shift moves the shift members 288 and 244 to the right andthrough the medium of the spring loaded ball 256, the synchronizing ring254 is brought into contact with the friction ring or cone 26 to stoprotation of the ring gear 226. Continued shifting movement toward theright will force the ball 256 out of its notch to bring the internalsplines or teeth on the shift member 244 into mesh with the teeth 282 onthe ring gear 226. Since the shift member 244 is restrained againstrotation by the spines 248 engaging the casing, the ring gear 226 isthus locked against turning movement. With the parts set in thisfashion, the power is transmitted from the driving element of thetransmission (main clutch element 32) through the member 2i8 to the sungear teeth 220. With the ring gear 226 locked against rotation, therotation of the sun gear 220 causes the planet carrier 224 to rotate inthe same direction as the sun gear but at reduced speed. Through themedium of the'teeth 230 the planet carrier 224 isright, after rod 288has been returned to neutral position. This shift operates to lock thecentral shaft 200 against rotation, due to the engagement of the shiftmember 212 with the stationary teeth 210, the synchronizing arrangementoperating in the same manner as that described in connection with thesynchronizing ring 254. Looking of the central shaft 200 operates tolock the sun gear 2i2 against rotation and power is transmitted from thering gear 2i8 to planets 2, which roll on the stationary sun gear andproduce rotation of the planet carrier 216 inthe same direction as thatof the ring gear 2l8 but at reduced speed. The hub 2l6a of this planetcarrier is splined directly to the driven sleeve 202 to which the poweris transmitted. It will be apparent that the gear reduction in thisinstance is less than in first speed since in the present instance theplanets are rolling on the stationary sun gearof relatively smalldiameter while in first speed the planets roll on a stationary ring gearof relatively large diameter.

To obtain the third or direct drive forward 1' speed, the shift rod 290is engaged and shifted to the left. This brings shift member 212 intoengagement with the teeth 266 on the clutch member fixed to the rear endof the driven sleeve.

the engagement taking place after the usual synchronizing action. drivensleeve to the central shaft 200. With these parts thus fixed againstrelative rotation, direct drive is transmitted from the ring gear member2i8 to the planets 2, which are restrained'against rotation about theirown axis. Consequently, the planet carrier H6 is rotated at the samespeed as the ring gear member H8 and drive is transmitted directly fromthe planet carrier to the driven sleeve 202.

, For reverse, the shift rod 288 is engaged and shifted to the leftafter rod 280 is returned to its neutral position. Shifting of rod 288to the left brings the internal splines or teeth on the shift member 244into engagement with the teeth 228 on the planet carrier 224, after theparts have been synchronized through the action of the ring 254. Theshift member 244 operates to hold the planet carrier 224 stationary anddrive is transmitted through the member 2i8 to the sun gear 220 whichrotates the planets 222 about their This operates to lock the i own axesin the stationary carrier 224. Reverse motion is thus imparted to thering gear 228. The shift to,the left .not only brings the shift member244 into engagement with the teeth 228, but also operates to bring theinternal teeth 242 on the shift member 238 into engagement with theteeth 232 on the ring gear 226. Thus, this ring gear 226 is coupled tothe shift member 238 and transmits reverse drive to this shift member,from which the reverse drive is transmitted to the driven sleeve 202through the hub 234.

The embodiment just described, like that described in conjunction withFigs. 1 to 5, thus provides the three forward speeds and reverse commonfor vehicle drives and including a direct drive forward top speed.

In each of the modifications, positive engagement of the parts isprovided for each of the various speeds and the difliculties anddisadvantages such as slipping and chattering. usually found inmuti-speed transmission arrangements employing gearing where one oranother of the elements of the gear mechanism are held against rotationby frictionally engaging brake bands or the like, are eliminated.

The described structures further enable the several available speeds tobe obtained selectively through the manipulation of a single selector tofour different positions which readily may be arranged to be reached. byoperation of a single gear lever of the usual kind which is manipulable-to the four corner positions of an H-type quadto 9, the planetary gearmechanism includes two trains of planetary gears rather than the singletrain of the form shown in Fig. 1, but by reference to the drawings itwill be apparent that the two train form is axially just as compact asthe single train form and provides an arrangement in which synchronizersare incorporated so that the shifts to the various different speeds maybe made without clashing engagement of positively engaging partsrotating at different speeds.

One embodiment characteristic of both forms of the transmission isparticularly to be noted. This characteristic is the provision of thecentral shaft member passing through the driven element of thetransmission which central shaft member provides a stationary reactionmember for holding a sun gear stationary in order to obtain a desiredspeed ratio through the transmission.

The transmission unit as a whole is further particularly advantageouswhen combined with the specific clutch construction illustrated since itwill be apparent that this particularly form of clutch not only provideslight weight driven parts havingrelatively little inertia, but alsopermits the central portion of the clutch structure to be utilized forthe reception of a part of the transmission mechanism, thus providing anexceedingly compact clutch and gear. Also, this type of clutch permitsthe clutch and transmission to be enclosed in a common housing, receiv-'ing its lubrication from the same system as that providing lubricationfor the engine. The clutch, being operated by liquid, does not have tobe separated from the lubricated parts of the transmission and since theoperating liquid is lubricating oil, any liquid which may possibly leakfrom the clutch may, without harm, leak into the transmission space. a

As will further be evident, the transmission is particularlyadvantageously adapted for unit construction wherein the change speedgear is combined in a single unit with a driving axle structure andgearing, since the spaced bearings for the driven element, which elementacts as a locating element for various parts of the transmissionincluding the central shaft and certain of the gear parts,advantageously provide a desirable straddle mounting for the powerdelivering gear of the transmission which constitutes the driving gearof the axle gear assembly. Thus the axial length from the center line ofthe axle shaft to .the flywheel end of the engine may be madeexceedingly short.

From the foregoing it will be evident that many changes in the specificconstruction and arrangement of parts may be made within the scope ofthe invention and it is accordingly to be understood that the inventionis not to be limited to the structures hereinbefore described by way ofexample but is to be considered as embodying all forms of structurefalling within the scope of the appended claims.

What is claimed is:

i. In a power transmission, a driving element, a driven element,planetary gear mechanism including a sun gear member, a ring gear memberand a planet carrying member, each of said members having teethassociated therewith, a casing providing a rotationally stationaryabutment, axially shiftable means rotationally fixed with respect tosaid casing and having teeth thereon, and means for selectively movingthe last mentioned means axially to engage the teeth thereon with theteeth of said planet carrying member, with the teeth of said ring gearmember, or with theteeth of said sun gear member to maintain theselected member stationary.

2. A power transmission comprising a casing, a driving element, a drivenelement, said driven element comprising a sleeve rotatably mounted insaid casing, planetary gear mechanism including a sun gear member, aplanet carrier member and a ring gear member for transmitting power fromsaid driving element to said sleeve, and means for selectively holdingeach of the members of said gear mechanism against rotation to providedifierent drives from the driving element to the sleeve, said meansincluding a central shaft extending through said sleeve to engage one ofsaid elements of said gear mechanism.

3. A unit power transmission having a single power input element fortransmitting power from an engine to an axle comprising a casing adaptedto be secured to the engine, planetary gear mechanism comprising a sungear, planet gears and a ring gear mounted in said casing to rotateco-axially with the engine shaft, said planet gear meshing only withsaid ring and sun gears, said planetary gear mechanism including adriven sleeve co-axial with the engine shaft and providing a .pluralityof speed reductions of different ratio between said power input elementand said sleeve, spaced apart bearings for rotatably mounting aid sleevein said casing, said gear mechanism being located in said casing betweenthe engine shaft and the nearest of said spaced apart bearings, and axlegears in said casing, said axle gears including an external gear on theportion of said sleeve between said bearings and a gear meshingtherewith and mounted to rotate about an axis at an angle to the axis ofsaid sleeve.

4. A unit power transmission having a single power input element fortransmitting, power from an engine to an axle comprising a casingadapted to be secured to the engine, planetary gear mechanism comprisinga sun gear, planet gears and a ring gear mounted in said casing torotate co-axially with the engine shaft, said planet gear meshing onlywith said ring and sun gears, said planetary gear mechanism including adriven sleeve and providing a plurality of speed reductions of differentratio between said power input element and said sleeve, said sleevebeing mounted in spaced apart bearings coaxial with the engine shaft,said-sleeve extending in overhung relation toward the engine shaft fromthe nearest one of said bearings, a central shaft member extendingthrough said sleeve and constituting a, reaction member for transmittingreaction from said gear mechanism to said casing to obtain one of saidspeed reductions, said central shaft member being located radially bysaid sleeve member and portions of said sleeve member and said centralshaft member between the engine shaft and the adjacent one of saidbearings serving to radially locate certain parts of said planetary gearmechanism, and an external gear on said sleeve member between saidbearings for driving an axle gear mounted to rotate about an axis at anangle to the axis of said sleeve.

5. A unit power transmission having a single power input element fortransmittingpower from an engine to an axle comprising a casing adaptedto be secured to the engine, planetary gear mechanism comprising a sungear, planet gears and a ring gear mounted in said casing to rotateco-axially with the engine shaft, said planetary gear mechanismincluding a driven sleeve co-axial with the engine shaft and providing aplurality of speed reductions of different ratio between said powerinput element and said sleeve, spaced apart bearings for rotatablymounting said sleeve in said casing, said gear mechanism being locatedin said casing between the engine shaft and the nearest of said spacedapart bearings, axle gears in said casing, said axle gears including anexternal gear on the portion of said sleeve between said bearings and agear meshing therewith and mounted to rotate about an axis at an angleto the axis of said sleeve, and means including a reaction memberpassing through said sleeve and engaging, on the side of said axle gearsremote from said gear, mechanism for selectively holding said sun gearrotationally stationary to obtain one of said speed reductions.

6. A power transmission including a driving element, a hollow drivenelement, planetary gearing including sun, planetand ring gears fortransmitting power at a plurality of speed reductions from the drivingelement to the driven element, a' rotationally stationary abutment, areaction member extending through said driven element, said reactionmember having fixed thereto a sun gear forming a part of said planetarygearing and means for selectively positively coupling said reactionmember to said abutment or to said driven member.

'7. A power transmission having a single power input element, a hollowdriven element coaxial eluding a reaction member extending through saiddriven element, said reaction member having fixed thereto a gearconstituting a sun gear of the planetary mechanism, and a brake forselectively positively coupling said reaction member to said abutment.

8. In a power transmission, a driving element, a driven element, aplanetary gear mechanism including a sun gear member, a ring gear memberand a planet carrying member, each of said members having clutch teeththereon, a casing providing a rotationally stationary abutment, anaxially shiftable member rotationally fixed with respect to said casingand having clutch teeth thereon, means for selectively moving the lastmentioned member axially in one direction from a neutral position toengage the teeth thereon with the teeth of said planet oarryingmember,and in the opposite direction from'said neutral position to engage theteeth thereon with the teeth on said ring gear member and means forselectively connecting the clutch teeth on said sun gear member with astationary abutment.

element, a driven element, planetary gear mecha-.

nism, a plurality of clutches operatively associated with said mechanismand selectively operable to provide a plurality of forward speeds ofdiil'erent ratio and a reverse speed between the driving element and thedriven element through said mechanism. means including three separateclutch shifting elements for controlling said clutches, and a commonactuating means movable to difi'erent positions to engage diflerentselected pairs of said shifting elements while remaining disconnectedfrom the remaining one of said shifting elements whereby to engage theclutches required to selectively obtain any one of said speeds.

10. A power transmission comprising a driving element, a driven element,a single planetary gear train, a plurality of clutches operativelyassociated with said gear train and selectively operable to provide aplurality of forward speeds of different ratio and a reverse speedbetween the driving element and the driven element through said geartrain, means including three separate clutch shifting elements forcontrolling said clutches, and a common actuating means movable todiilerent positions to engage different selected pairs of said shiftingelements while remaining disconnected from the remaining one of saidshifting elements whereby to engage the clutches required to selectivelyobtain any one of said speeds.

11. A power transmission comprising a driving element, a driven element,a single planetary gear train, a plurality of positively engagingclutches operatively associated with said gear train having partsaxially shiftable to enaage the clutches, means comprising threediiferent shift members ior selectively engaging different clutches toobtain a plurality of forward speeds of diflerent ratio and a reversespeed between the driving element and the driven element through saidgear train, three axially movable shift rods each connected to adifferent one of said shift members, said rods being arranged paralleland adjacent to each other, and an axially and tumably mounted selectormounted to engage different pairs of said shift rods when turned todifferent positions, whereby to simultaneously shift a selected pair ofrods when the selector is moved thereafter axially.

12. A power transmission comprising a driving element, a driven element,a stationary abutment, 9, single planetary gear train comprising a sungear, a ring gear and a plurality of planets mounted on a planetcarrier, clutch means for connecting the planet carrier to said drivenelement, and means for selectively connecting either one of said gearsto the driven element and the remaining one of the said gears to saidabutment.

13. A power transmission including a .single driving element, a singlehollow driven element, planetary gearing including a sun gear fortransmitting power from the driving element to the driven element, arotationally stationary abutment and means including an axiallyshiftable reaction member extending through said 'driven element forselectively coupling said sun gear to said abutment.

' 14. In a power transmission, a casing providing a reaction absorbingabutment, a driving element, a driven element, a single planetary gearset comprising a ring gear member, a planet system including a planetcarrier and an annular sun gear member, a rotationally stationary andaxially shiftable central. shaft member, brake means associated withsaid sun gear member and said central shaft member and positivelyengageable when the central shaft member is shifted in selecteddirection to hold said sun gear member against rotation, clutch meansassociated with said driving element and said ring gear member andpositively engageable to transmit power from the driving element to thering gear member and clutch means associated with said planet carrierand said driven element and positively engageable to transmit power.

15. In a power transmission, a driving element, a driven element,planetary gear mechanism ineluding a sun gear member, a ring gear memberand a planet carrying member, each or said members having teeth thereon,a casing providing a rotationally stationary abutment, an axiallyshiftable member rotationally flxed with respect to said casing andhaving teeth thereon, and means for selectively moving the lastmentioned member axially in one direction from a neutral position toengage the teeth thereon with the teeth of said planet carrying memberand in the opposite direction from said neutral position to engage theteeth thereon with the teeth on said sun gear member.

ANDRE J. MEYER.

R088 2. TAYLOR.

